Two Apple veterans, co-founders of Aeva, have built a sensor for self-driving cars that can see not just where things are but how fast they’re moving—a potentially critical ability for cars trying to navigate safely around other cars and pedestrians.
Conventional LIDAR sensors transmit pulses of laser light—and measure the time it takes for the light to bounce back to estimate how far away surrounding objects are.
The frequency difference between the incoming and outgoing beams is directly proportional to the distance that the incoming beam traveled before reflecting back. Optical combination of these beams is used to more precisely estimate the distance compared to conventional LIDAR.
To compensate for velocity-related redshift of signals, FMCW LIDARs take two successive measurements: one from a signal with a rising frequency and a second from a signal with a falling frequency. Aeva’s LIDAR compiles the data streams from the two signals into a single image, correlated down to the pixel and the nanosecond.
The ability to accurately measure velocity is an important breakthrough for autonomous vehicles. Most of those vehicles use radar sensors to measure the movement of nearby objects—but the images those sensors produce tend to have a much lower resolution than those of LIDAR. In contrast, Aeva’s high-resolution LIDAR can analyze those same objects with more detailed resolution to determine which ones are moving, as well as their speed and direction.
Aeva claims its FMCW-based approach will make the vehicle’s AI better able to operate safely, is more resistant to interference from other nearby LIDARs, and will give the vehicle data that approaches camera-like resolutions.
“Our new proprietary 4D LiDAR technology possesses the best of both worlds,” said Mina Rezk, one of Aeva’s co-founders. “We are able to not only improve the performance of traditional LiDARs, but also give each LiDAR point an instantaneous measurement of velocity, unlocking the temporal element that is often overlooked and missed.”
Rezk’s startup will have competition in the FMCW LIDAR market. Last year, GM bought the startup Strobe that seems to be using the same approach. And another company called Blackmore is also selling an FMCW technology.
Aeva has already started selling its LIDARs to OEMs and vehicle manufacturers. The company is working on reducing the size of the device and preparing its final design.
Want to find out more about LIDAR technology? Check out New LIDAR Driving System Lets Vehicles “Gaze” Like Humans.